This core has two major roles: (1) to provide biostatistical support to the research projects on this program project, including study design and sample size calculation, data summarization, statistical programming, and analysis and reporting; and (2) to provide centralized data coordination and database support for the clinical trials conducted under this program project, including those being done through a cooperative network of collaborating institutions. Part of the staff of this core work within the Clinical Statistics program of the Clinical Research Division. Clinical Statistics supports centralized data abstraction for all patients treated within the division, maintains a central database for patient and canine data, and provides statistical and computing support to the Clinical Research Division. This activity is complemented for purposes of this core by a staff dedicated to clinical trials in transplants after nonmyeloablative conditioning, most of which are being conducted within a network of collaborating institutions, with the FHCRC serving as coordinating center.